Apparatus for exerting equalized compressive forces



March 31, 19 e. E. MILLER I 3, 7,

APPARATUS FOR EXERTING EQUALIZED COMPRESSIVE FORCES Filed June 19, 1961 2 Sheets-Sheet 1 //v VEN TOE 6.5. M/L L E B BY 9531M March 31, 1964 e. E. MILLER 3,127,162

APPARATUS FOR EXERTING EQUALIZED COMPRESSIVE FORCES Filed June 19, 1961 2 Sheets-Sheet 2 /NVENTOE G.E. MILLER ATTORNEY United States Patent Office 3,127,162 Patented Mar. 31, 1964 3,127,162 APPARATUS FOR EXERTING EQUALIZED CGWREdSiVE FORCES Gienn E. Miiier, Roeirhrooir Heights, Nehru, assignor to Western Etectric Company, Incorporated, a corporation of New York Filed dune 19, 1961, Ser. No. 118,118 6 Qiairns. (Cl. 269157) The present invention relates generally to apparatus for exerting equalized compressive forces on a stack of articles at two spaced points on the outer surface thereof; and more particularly to apparatus for exerting equalized compressive forces on a relay pile-up at two spaced points on the upper surface thereof, the character of the pile-up being such that the elevation or compressibility may be different at the pressure points involved. Accordingly, the general objects of the invention are to provide new and improved apparatus of such character.

In the assembly of wire spring relays, the components of the pile-up (lead wires, insulation blocks, contact points, and leaf springs) are assembled in proper align ment on a base plate and are secured thereto under a cover plate by a pair of spaced fasteners drawn tight in the base plate. Though the leaf springs are necessary to bias the contacts to a normally open position in the completed relay, they make it difficult for the fasteners to be inserted and drawn tight since the resilient pile-up must first be compressed. The compressing of the relay pile-up presents a difficult task, however, because the pileup is often of uneven elevation and of different compressibility across the upper surface thereof.

In the past, because of the difficulty in assembling and compressing the pile-up, the assembly required two separate bench positions. The pile-up was assembled in proper alignment at a first bench position and transported by a conveyor to a second bench position where the assembled pile-up was compressed, while the fasteners were inserted therethrough and tightened in the base plate. Obviously, it would be greatly desirable if the time wasted in transporting the pile-ups from the first bench position to the second could be avoided.

Therefore, a more specific object of the invention is to provide new and improved apparatus for exerting equalized compressive forces on a relay pile-up at two spaced points on the upper surface thereof, the character of the pile-up being such that the elevation or compressibility may be different at the pressure points involved, which apparatus permits the assembly and compression operations to be accomplished at one bench position.

With the foregoing and other objects in mind and in accordance with certain aspects of the invention, equalized compressive forces are exerted at two spaced points on the outer surface of articles stacked on a base by a lever having a bifurcated end for engaging the surface at two points laterally spaced equidistant from and on opposite sides of a longitudinal centerline of the lever. A universal coupling, connecting the lever ata point along the longitudinal centerline to the base, forms a fulcrum about which the lever may pivot both laterally and longitudinally of itself, as required, to exert equalized compressive forces at the two points. A mechanism is provided along the centerline for pivoting the lever about the universal coupling to exert compressive force on the stack of articles.

According to certain more specific aspects of the invention, the equalized compressive forces are exerted on a relay pile-up, the character of which is such that the elevation or compressibility may be different at the pressure points involved. The above-mentioned lever is provided with a hemispherical socket intermediate the ends thereof, the socket forming a counterbore terminating a bore extending through the lever. A fastener having a hemispherically shaped head is slidably received through the bore in the lever so that the hemispherically shaped head is received in the socket to form a fulcrum about which the lever may pivot. The fastener is mounted in a base in adjustable relationship toward and away therefrom and the lever is spring biased so that the socket is maintained in constant contact with the hemispherically shaped head. The adjustable height of the fastener head with respect to the base, and the biased contact of the fastener head and the socket, allow the lever to accommodate various size relay pile-ups and exert various pressures thereon.

Other objects, advantages, and aspects of the invention will appear from the following detailed description of a specific embodiment thereof, when taken in conjunction with the appended drawings, in which:

FIG. 1 is a perspective view of a fixture for compressing a relay pile-up, which fixture is a preferred embodiment of the invention;

FIG. 2 is a front view of the fixture, with the relay pileup clamped therein, having portions broken away to reveal details of construction;

FIG. 3 is a fragmentary left-side view, partly in section, taken along the line 3-3 of FIG. 2;

FIG. 4 is a fragmentary right-side view of the fixture, having portions broken away for clarity; and

FIG. 5 is a simplified, somewhat schematic view similar to FIG. 3, illustrating the operation of the apparatus in applying equalized compressive forces against an uneven workpiece.

Referring now in detail to the drawings and particularly to FIGS. 1 and 2, there is illustrated one specific embodiment of the invention in which a lever 11 is designed to exert equalized compressive forces on a relay pile-up 11 at two spaced points on the upper surface thereof. The lever 10 has a bifurcated end 12 for engaging the surface at two points laterally spaced equidistant from and on opposite sides of a longitudinal centerline B of the lever, and a tapered end 13 opposite the bifurcated end. The tapered end 13 is provided with an aperture 14 extending therethrough; and, intermediate the two ends 12 and 13 and along the centerline B, a hemispherical socket 16 is provided which forms a counterbore terminating a bore 17 also extending through the lever N.

A fastener 18 having a hemispherically shaped head 19 is slidably received through the bore 17 in the lever 10 so that the hemispherically shaped head 19 is received in the socket 16 to form a fulcrum about which the lever 16) may pivot both about a lateral axis A and the centerline B, as required, to exert equalized compressive forces at the two spaced points. The bore 17 is oversize so as to readily facilitate substantial universal pivotal movement of the lever about the head 19 of the fastener 18. The fastener 18 is threadedly secured in a base 21 so that the head 19 of the fastener 18 is adjustable toward and away therefroa and has mounted therearound a helical compression spring 22 between the lever 10 and the base 21 for biasing the socket 16 into constant contact with the hemispherically shaped head 19. The adjustable height of the fastener head 19 with respect to the base 21 and the biased contact of the socket 16 and the head 19, enable the lever 10 to accommodate various size relay pile-ups and exert various pressures thereon.

Referring now to FIGS. 2 and 4, a cam follower 23, mounted at the tip of the tapered end 13 along the centerline B of the lever 10 and riding on a rotary cam 24, pivots the lever 10 about the hemispherically shaped fastener head 19 (the lateral axis A in FIG. 1) to exert compressive force on the relay pile-up 11 when the rotary cam 24 is actuated by a handle 26 secured thereto. A threaded fastener 27 (FIGS. 1 and 2) extends slidably through the aperture 14- of the lever 10, and is threaded into the base 21. A helical compression spring 28 is mounted around the fastener 27, between a head 29 thereof and the lever 19 for biasing the tapered end 13 of the lever downward so that the cam follower 23 remains in constant contact with the cam 24 so as to hold the lever open in a receiving position when no pile-up 11 is being clamped. The aperture 14 is oversize and elongated, as illustrated in FIGS. 1 and 2, to permit substantial pivoting movement of the lever about its lateral axis A and a smaller degree of pivoting movement about its longitudinal centerline B where needed to equalize pressure.

A piece-part support slide 31 is provided with a recess 32, a pair of dowel-like extensions 3333, and a pair of step-like corners 343-4 for enabling accommodation and assembly of the relay pile-up 11 in proper alignment. When assembled, the pile-up 11 and the slide 31 are moved to the right, as viewed in FIGS. 1 and 2, along the base 21 to a rest position (FIG. 2) beneath the bifurcated end 12 of the lever 10.

Operation After the pile-up 11 has been assembled and moved to the rest position on the slide 31, the handle 26 is turned to thereby pivot the lever 10 about the lateral axis A (according to the curved arrow C in FIGS. 1 and 2) until the tips 3535 of the bifurcated end 12 engage the upper surface of the pile-up 11 at the two spaced points shown in FIG. 3. Assuming that the upper surface of the pile-up 11 is perfectly level or horizontal, as is normally the case and as is indicated by the reference line D in FIG. 3, the tips 35-35 engage the pile-up simultaneously and compress the same from the two spaced points to a level and with a force determined by the shape of the cam 24 and the adjusted height of the hemispherical head 19 above the base 21.

A pair of screws 36-36 (FIG. 3) are then inserted in the pile-up 11 and drawn tight thereto by pneumatic screwdrivers 37-37. In this manner, it is obvious that the relay pile-up may be assembled and compressed at a single bench position.

Assuming now that the upper surface of the pile-up 11 is uneven, as often happens and as is indicated in exaggerated fashion for illustrative purposes by the slanted reference line B in FIG. 5, the right-hand tip 35 first engages and is stopped by the surface of the pile-up 11 as the lever pivots downward about the lateral axis A from the phantom-line position to the solid line position. Upon further downward pivoting movement, the lever pivots about the longitudinal centerline B (as indicated by the curved arrow F in FIGS. 1 and until the lefthand tip 35 also engages the pile-up 11, at which time the lever assumes the canted attitude illustrated in solid lines in FIG. 5.

After contact has been made by both the tips 3535, further downward pivoting movement under the influence of the cam 24 causes the lever tips 3535 to compress the pile-up with equalized pressure at both points, while maintaining the canted attitude where the compressibility is equal at the two spaced points.

Assuming that the compressibility is different at the two points involved (thus, the right side of the pile-up 11 in FIG. 5 would probably compress more easily than the left side), then the lever pivots about the longitudinal centerline B during compression as any unevenness in compressibility occurs to maintain contact with the surface and apply the equalized pressures.

While one specific embodiment of the invention has been described in detail hereinabove, it will be obvious that various modifications may be made from the specific details described without departing from the spirit and scope of the invention.

What is claimed is:

1. Apparatus for exerting equalized compressive forces on a stack of articles at two spaced points on the outer surface thereof, which comprises a base for supporting the stack of articles; a lever having a bifurcated end for engaging the surface at two points laterally spaced equidistant from and on opposite sides of a longitudinal centerline of said lever; a universal coupling connecting said lever at a point along the longitudinal centerline to said base to form a fulcrum about which the lever may pivot both longitudinally of itself, to exert compressive forces on the stack of articles, and laterally of itself to equalize the compressive forces between the two spaced points; and means disposed along the centerline for pivoting said lever about said universal coupling to exert compressive force on the stack of articles.

2. Apparatus for exerting equalized compressive forces on a stack of articles at two spaced points on the outer surface thereof, which comprises a base for supporting the stack of articles; a lever having a bifurcated end for engaging the surface at two points laterally spaced equidistant from and on opposite sides of a longitudinal centerline of said lever; a universal coupling connecting said lever at a point along the longitudinal centerline to said base to form a fulcrum about which the lever may pivot both longitudinally of itself, to exert compressive forces on the stack of articles, and laterally of itself to equalize the compressive forces between the two spaced points; a cam follower mounted along the centerline at the end of said lever opposite the bifurcated end; a rotary cam, upon which said cam follower rides, for pivoting said lever about said coupling to exert compressive force on the stack of articles; and resilient means for biasing said lever so that said cam follower remains in constant contact with said cam.

3. Apparatus for exerting equalized compressive forces on a stack of articles at two spaced points on the outer surface thereof, which comprises a base for supporting the stack of articles; a lever having a bifurcated end for engaging the surface at two points laterally spaced equidistant from and on opposite sides of a longitudinal centerline of said lever, and having a hemispherical socket intermediate the ends and along the longitudinal centerline of the lever; a ball member fixed to said base and received in the socket of said lever to form a fulcrum about which the lever may pivot both longitudinally of itself, to exert compressive forces on the stack of articles, and laterally of itself to equalize the compressive forces between the two spaced points; resilient means for biasing said lever and said ball member together so that said ball member remains in constant contact with the socket; and means disposed along the centerline for pivoting said lever about said fulcrum to exert compressive force on the stack of articles.

4. Apparatus for exerting equalized compressive forces on a stack of articles at two spaced points on the outer surface thereof, which comprises a base for supporting the stack of articles, a lever having a bifurcated end for engaging the surface at the two points laterally spaced equidistant from and on opposite sides of a longitudinal centerline of said lever, and having a hemispherical socket provided intermediate the ends and along the longitudinal centerline thereof; a ball member fixed to said base and received in the socket of said lever to form a fulcrum about which said lever may pivot both longitudinally of itself, to exert compressive forces on the stack of articles, and laterally of itself to equalize the compressive forces between the two points; resilient means for biasing said lever and said ball member together so that said ball member remains in constant contact with the socket; a cam follower mounted along the centerline at the end of said lever opposite the bifurcated end; a rotary cam, upon which said cam follower rides, for pivoting said lever about said ball member to exert compressive force on the stack of articles; and resilient means for biasing said lever so that said cam follower remains in constant contact with said cam so as to hold said lever open in a receiving position when no articles are being clamped.

5. The apparatus as recited in claim 3, wherein the hemispherical socket is in the upper surface of the lever and forms a counterbore terminating a bore extending through the lever; wherein the ball member comprises a fastener having a hemispherically shaped head, which fastener is slidably received through the bore in the lever so that the hemispherically shaped head is received in the socket, said fastener being mounted in said base in adjustable relationship therewith; and wherein the resilient means comprises a helical compression spring mounted about said fastener between said base and the lever for biasing the socket in constant contact with the hemispherically shaped head so that, by adjusting the height of the fastener head with respect to said base, the lever can accommodate various size stacks of articles and exert various pressures thereon.

6. Apparatus for exerting equalized compressive forces on a relay pile-up at two spaced points on the upper surface thereof, the character of the pile-up being such that the elevation or compressibility may be different at the pressure points involved, which apparatus comprises a lever having a bifurcated end for engaging the surface at the two points spaced equidistant from and on opposite sides of a longitudinal centerline of said lever, a tapered end opposite the bifurcated end, and a hemispherical socket in the upper surface along the centerline and intermediate the two ends thereof, the socket forming a counterbore terminating a bore extending through said lever; a fastener having a hemispherically shaped head,

which fastener is slidably received through the bore in said lever so that the hemispherically shaped head is received in the socket to form a fulcrum about which said lever may pivot both longitudinally of itself to exert compressive forces on the stack of articles, and laterally of itself to equalize the compressive forces between the two points; a base whereon the pile-up may be supported and wherein said fastener is mounted in adjustable relationship toward and away therefrom; a helical compression spring mounted about said fastener between said base and lever for biasing the socket into constant contact with the hemispherically shaped head so that, by adjusting the height of the fastener head with respect to said base, said lever can accommodate various size relay pile-ups and exert various pressures thereon; a cam follower mounted along the centerline at the tip of the tapered end of said lever; a rotary cam, upon which said cam follower rides, for pivoting said lever about the hemispherically shaped head of said fastener to exert compressive force on the relay pile-up; and resilient means mounted on said base for biasing said lever so that said cam follower remains in constant contact with said cam so as to hold said lever open in receiving position when no pile-up is being clamped.

References Cited in the file of this patent UNITED STATES PATENTS 2,325,387 Fredrickson July 27, 1943 2,384,148 Yeager Sept. 4, 1945 2,519,984 Speaker Aug. 22, 1950 2,690,088 Wiglesworth Sept. 28, 1954 

4. APPARATUS FOR EXERTING EQUALIZED COMPRESSIVE FORCES ON A STACK OF ARTICLES AT TWO SPACED POINTS ON THE OUTER SURFACE THEREOF, WHICH COMPRISES A BASE FOR SUPPORTING THE STACK OF ARTICLES, A LEVER HAVING A BIFURCATED END FOR ENGAGING THE SURFACE AT THE TWO POINTS LATERALLY SPACED EQUIDISTANT FROM AND ON OPPOSITE SIDES OF A LONGITUDINAL CENTERLINE OF SAID LEVER, AND HAVING A HEMISPHERICAL SOCKET PROVIDED INTERMEDIATE THE ENDS AND ALONG THE LONGITUDINAL CENTERLINE THEREOF; A BALL MEMBER FIXED TO SAID BASE AND RECEIVED IN THE SOCKET OF SAID LEVER TO FORM A FULCRUM ABOUT WHICH SAID LEVER MAY PIVOT BOTH LONGITUDINALLY OF ITSELF, TO EXERT COMPRESSIVE FORCES ON THE STACK OF ARTICLES, AND LATERALLY OF ITSELF TO EQUALIZE THE COMPRESSIVE FORCES BETWEEN THE TWO POINTS; RESILIENT MEANS FOR BIASING SAID LEVER AND SAID BALL MEMBER TOGETHER SO THAT SAID BALL MEMBER REMAINS IN CONSTANT CONTACT WITH THE SOCKET; A CAM FOLLOWER MOUNTED ALONG THE CENTERLINE AT THE END OF SAID LEVER OPPOSITE THE BIFURCATED END; A ROTARY CAM, UPON WHICH SAID CAM FOLLOWER RIDES, FOR PIVOTING SAID LEVER ABOUT SAID BALL MEMBER TO EXERT COMPRESSIVE FORCE ON THE STACK OF ARTICLES; AND RESILIENT MEANS FOR BIASING SAID LEVER SO THAT SAID CAM FOLLOWER REMAINS IN CONSTANT CONTACT WITH SAID CAM SO AS TO HOLD SAID LEVER OPEN IN A RECEIVING POSITION WHEN NO ARTICLES ARE BEING CLAMPED. 